﻿#region Copyright 2010-2011 by Roger Knapp, Licensed under the Apache License, Version 2.0
/* Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#endregion
using System;
using System.Collections.Generic;
using System.IO;
using CSharpTest.Net.Processes;

namespace CSharpTest.Net.CustomTool.CodeGenerator
{
	static class AssemblyRunnerCache
	{
		[ThreadStatic]
		static Dictionary<string, WeakReference> _domains;

		public static IRunner Fetch(string exe)
		{
			if (_domains == null)
				_domains = new Dictionary<string, WeakReference>(StringComparer.OrdinalIgnoreCase);

			exe = Path.GetFullPath(exe);
			WeakReference wref;
			AssemblyRunner worker;

			if (!_domains.TryGetValue(exe, out wref) || !wref.IsAlive || null == (worker = wref.Target as AssemblyRunner) || worker.IsDisposed)
				_domains[exe] = new WeakReference(worker = new AssemblyRunner(exe));

			GC.KeepAlive(worker);
			return worker;
		}
	}
}
